The definition of well to do is someone who is wealthy or who is prosperous.(adjective)
An example of well to do is how you would describe Bill Gates or anyone else with lots of money.
See well-to-do in Webster's New World College Dictionary
See well-to-do in American Heritage Dictionary 4
Origin: From the phrase well to do in the world
Origin: : well2, prosperous, affluent
Origin: + to, for
Origin: + do1, doing.
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